figure a

References: 1. The WHO Epilepsy Fact Sheet No. 999.; 2. Thurman, D. J. See, go.nature.com/2spiwk; 3. Ngugi, A. K. et al; Epilepsia 51, 883–890 (2010).

figure b

4. Engel, J. Jr. et al. J. Am. Med. Assoc. 307, 922–930 (2012).; 5. Arif, H. et al. Arch. Neurol. 67, 408–415 (2010).; 6. LaFrance, W. C. Jr., Kanner, A. M. & Hermann, B. Int. Rev. Neurobiol. 83, 347–383 (2008).; 7. Meador, K. J. et al. Neurology 77, 1305–1307 (2011).